There is no question that US journalism completely failed in its job during the run up to the war in Iraq. As Nitpicker puts it:

Journalism is supposed to “change the course of events”! In a free society, journalism should be the means by which an informed public decides which direction they want their nation to take. What is that, if not changing the course of events? In fact, that’s why people like me were so disappointed with the media before the Iraq war. If they’d done their job better . . . 2,800 American service members and hundreds of thousands of Iraqis would still be alive.
And we’d have fewer terrorists.